If you are using the Windows 10 on your computer or Laptop as the operating system, then you do not need to use any other email client, because of the Windows 10 operating have the default email app.
In this tutorial, we are going to share how to change the windows 10 email app default signature with the screenshot. Follow the below steps to change the default signature to your custom signature.
Step 1) Open the Mail app and click on the Settings (gear icon) => Signature option.
Step 2) If you want to use the same signature for your accounts, then you can just not use a signature by flipping the Use an email signature switch to Off.
After saving the signature, your signature will appear in all your emails.